1. Field of the Invention
The present invention relates to a data storage device which stores data composed of a plurality of bits.
2. Description of the Related Art
Various kinds of data storage devices including also a data holding circuit such as a latch circuit which temporarily stores data have been proposed and put to practical use. However, most of these data storage devices stores one bit data by one storage element or one storage device. For example, in a D-type flip-flop, a signal level indicating a level "H" or a level "L" at a D input terminal is stored by applying clocks thereto. If the level "H" or the level "L" is being inputted to the D input terminal at a certain timing of rising up edges of the clocks, the level "H" or the level "L" is outputted from a Q-output terminal, and until a next timing of the rising up edge of the clocks, an output level at the Q-terminal is kept at the level "H" or the level "L" that is being outputted. As described above, one flip-flop can output only the two signal levels "H" or "L". Accordingly, by corresponding the two signal levels to "1" or "0", one bit data is stored in one storage circuit.